Asymmetric 1,3-dipolar cycloadditions

Metalated heterocycles and their applications in synthetic organic chemistry.

The synthesis of polyhydroxylated indolizidines and pyrrolizidines belonging to the class of iminosugars, endowed with a vast and assorted biological activity, can be achieved in a straightforward manner by a general strategy consisting of a highly stereoselective 1,3-dipolar cycloaddition of polyhydroxylated pyrroline-N-oxides followed by simple transformations of the isoxazolidine adducts The strategy allows the complete control of the relative and absolute stereochemistry of the numerous stereogenic centers decorating these compounds

Stereocontrolled Cyclic Nitrone Cycloaddition Strategy for the Synthesis of Pyrrolizidine and Indolizidine Alkaloids

Recent Developments in the Ferrier Rearrangement

This review is the third update of the original review, published in 1999, on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings the topic to the end of 2004. Both fundamental studies and applications are covered. The main topics include methodological developments, matrices, fragmentation of carbohydrates and applications to large polymeric carbohydrates from plants, glycans from glycoproteins and those from various glycolipids. Other topics include the use of MALDI MS to study enzymes related to carbohydrate biosynthesis and degradation, its use in industrial processes, particularly biopharmaceuticals and its use to monitor products of chemical synthesis where glycodendrimers and carbohydrate-protein complexes are highlighted.

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Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2003-2004

Covering: 1990–June 2002
 This review aims to summarise key features of the synthesis and 1,3-dipolar cycloaddition reactions of carbohydrate derived nitrones and oximes, allowing access to isoxazolines and isoxazolidines. An alternative approach to these targets, which involves the reaction of non-carbohydrate dipoles with carbohydrate derived alkenes, is also described.

1,3-Dipolar cycloaddition reactions of carbohydrate derived nitrones and oximes

Stereoselective entry to beta-linked C-disaccharides using a carbon-Ferrier reaction.

The effects of several novel monosaccharides upon thymidine incorporation into both normal and tumour cells were investigated. The monosaccharide 2-deoxy-3-[1-(R)-(ethoxycarbonyl)ethyl]- alpha-D-allo-pyranose had the most inhibitory effect on proliferation, with the (S)-enantiomer having less inhibitory effects. The chiral centre at carbon-7 was found to be an important part of the molecule, as 2-deoxy-3-[methoxycarbonyl methyl]-alpha-D-allo-pyranose had greatly decreased anti-proliferative properties in comparison with the parent compound. In addition, the 2-deoxy structure at carbon-2 was also found to be important, as 3-[1-(S)-(ethoxycarbonyl)ethyl]-alpha-D-allo-hexopyranose had greatly decreased inhibitory properties in comparison with the parent compound. The results indicate that these novel monosaccharides possess potent anti-proliferative properties, related to their chiral carbon-7 and 2-deoxy carbon-2 structure and suggest that further substitutions of the functional group at carbon-7 may improve these properties and possibly produce inhibitor selectivity for tumour cells in preference to normal cells.

Novel monosaccharides as potent inhibitors of cell proliferation.

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Natasha Gemmell

Papers

1,3-Dipolar cycloaddition reactions of carbohydrate derived nitrones and oximes

Stereoselective entry to beta-linked C-disaccharides using a carbon-Ferrier reaction.

Novel monosaccharides as potent inhibitors of cell proliferation.

Stereoselective Entry to β‐Linked C‐Disaccharides Using a Carbon‐Ferrier Reaction.

1,3-Dipolar Cycloaddition Reactions of Carbohydrate Derived Nitrones and Oximes